Covering devices that provide either stationary protection nixed in relation to the ground) or portable protection (i.e., mobile in relation to the ground) for shading, rain, dust, etc. are known. Examples of stationary or fixed covering devices, which are substantially larger than the mobile and portable covering devices, include fixed shading devices, umbrellas, and/or parasols used as an accessory to outdoor furniture. Examples of mobile covering devices include portable umbrellas, visors, etc.
The present invention relates to stationary covering devices that because of their larger size are subject to different functional requirements when compared to mobile and portable covering devices. Typically, prior art stationary covering devices have canopies with symmetrically shaped covers that can rotate about a longitudinal axis that provide symmetrical and equidistant cover extensions from a central vertex point. Exemplary conventional canopies have round, square, or polygonal symmetrical shapes. Such covering devices that embody the aesthetics of symmetry, fail to provide the function of a covering and shading device, namely, convenient and effective security and protection (e.g., from the sun) for the persons and things beneath the covering device. The inventor of the present invention has recognized that the symmetrical shape of the conventional canopies does not provide consistent shading throughout the year, particularly during the hottest months when people tend to spend the most time outdoors, and when the most direct solar radiation and related ultra violet levels are at their highest. Furthermore, the symmetrical shape of the conventional canopies does not provide consistent protection in lower latitudes (e.g. tropical and sub-tropical locales), where people tend to spend more time outdoors both on a daily, and subsequently, an annual basis, and where the solar radiation and related UV levels are stronger, as compared to higher latitudes, throughout the year. As explained later in detail, the lack of effective shading is especially apparent when viewed with the inconveniences of relocating shading targets or moving large-size stationary covering devices in order to enjoy consistent shading at a fixed location. For example, people sitting around a outdoor table that is shaded by a prior art symmetrically shaped canopy have to be moved to within the moving, small shaded area, consequently, leaving a few people without effective shading, at least in part, and/or exposing food or items to harmful sun exposure.
Some conventional covering devices use a tilt function in an attempt to correspondingly position the canopy relative to position of the sun. However, even with the symmetrical canopy in a tilted position, the shading targets underneath the covering device would still need frequent change of position in order to avoid sun's damaging rays throughout the day. This movement is required mainly because the position of the sun relative to shading targets constantly changes, and the fact that a symmetrical device is not designed to intercept the predictable angles of solar incidence.
In one mobile or portable application, U.S. Pat. No. 4,597,400 to Trudeau discloses a portable umbrella that looks like a baseball hat when extended. The brim of the baseball cap umbrella is present merely to create a resemblance to a baseball cap. U.S. Pat. No. 4,838,290 to Wu modifies the Trudeau patent to allow the user of portable umbrella to have a clear line of vision under a flat brim. However, there is no teaching or suggestion in Trudeau or Wu regarding the application of the disclosed concept to either fixed or stationary covering devices. In fact, the disclosed umbrella designs are intended for mobile and portable applications in which a user carries the umbrella with them, on their person. Therefore, neither the Trudeau nor the Wu designs are intended to service a stationary location. Furthermore, these designs do not take into account the solar angles related to the changing position of be sun throughout daylight hours.
U.S. Pat. No. 5,564,453 to Steiner discloses a umbrella having a symmetrically shaped canopy that is adjustable and/or extendible. The adjustable canopy allows for placement of the umbrella against a wall, for example, and can be adjusted to various sizes. It does not, however, account for any solar angles. Therefore, even though the canopy can be adjusted, there will still be areas underneath the apparatus that will not be shaded depending on the location of the sun and the time of the day.
U.S. Design Pat. No. 419,759 to Goudarzi discloses a non-stationary, handheld, octagonal, ornamental design for a rain umbrella. Once again, this ornamental design is primarily aesthetic and fails to consider predictable solar angles.
U.S. Pat. No. 5,505,221 to Gao discloses a non-stationary handheld umbrella with an asymmetrical, off-center support. The asymmetry and projecting visor edge create a protection zone when the umbrella is carried by the user, such that, instead of the umbrella shaft, the head and shoulders of the user would be directly under the center of the covering device. Because of its portable (non-stationary) design, however, the canopy of this umbrella design is not shaped to take into account the position of the sun or for creating a shading zone in a fixed location.
FIG. 1 shows a conventional stationary covering device that provides shading for shading targets at a particular time of day and year at a particular locale and latitude. In this case, the solar angles shown in FIG. 1 are those occurring on June 21, at 2 o'clock p.m. The covering device has a canopy 110 that is symmetrical about a support pole 120 in the center of a table 130 surrounded by shading targets defined by four chairs 140, 150, 160 and 170. As shown, in one furniture arrangement, two chairs 140 and 150 are positioned in direct sunlight and two other chairs 160 and 170 are in a shaded zone 180. In order for all four chairs 140, 150, 160 and 170 to be in the shaded zone 180 they would have to be either placed extremely close to one another or partially away from the table. Therefore, the use of symmetrically shaped canopies according to the prior art either exposes one or more people seating on the chairs to the harmful rays of the sun or causes overcrowding that would subject the people to uncomfortable seating arrangement within the shaded zone 180. Furthermore, a portion of the table 130 is also exposed to direct sunlight which would cause food, beverages, and other items to overheat, melt, or even spoil due to direct exposure to the sun. At certain times of the day, such as early morning or late afternoon, all four chairs would need to be located completely away from the fixed location table in order for them to be within the shaded zone. The fixed shading target zone 100 is not protected during the day.
The Environmental Protection. Agency, the World Health Organization, and other governmental and advisory agencies advise that over-exposure to ultraviolet radiation from the sun will lead to serious health risks, including skin cancer, premature aging of the skin and eye damage.
The best way to prevent these serious health risks, without staying indoors at all times, is to limit exposure to direct sunlight and to seek cover so as not to be directly exposed to the sun when spending time outdoors. The limitations presented by the prior art symmetrical covering devices do not provide effective shading at a fixed location without the inconvenience associated with either frequently moving shading targets (people, chair, etc.) or the shading device throughout the day.
Thus, there has been a long felt need in the art to solve the problem of creating an economical, stationary covering device of adequate size that will provide maximum and consistent protection or shading with minimum movement. None of the prior art devices adequately have solved this problem, either alone, or in combination with one another. In short, there exists a need for a stationary, convenient and simple approach to stationary covering devices that does not suffer from the aforementioned drawbacks of the prior art in terms of convenience, complexity, excess movements, labor, cost, etc.